Replacing the intake manifold

I've got it all tore down and I'm ready to order parts. I've looked at Dorman gasket sets and like the fact that they come with replacement bolts but I feel better using Felpro.
http://www.autozone.com/autozone/parts/Felpro-Intake-Manifold-Gasket/_/N-jad59Z93xym?itemIdentifier=723218_259704_19388_

Should I replace any bolts/seals or anything else while I've got it opened up?
Definitely replacing the thermostat.

What about the seals on the valve cover bolts? Fuel injector o rings?

Spark plugs/wires have 20K on them.